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While fetching data and storing it into sqlite db the UI of my app freezes

Hello My app is freezes ui for some seconds while it is fetching data from network and stores it in db and then shows it in recyclerview. For fetching data from network I am using retrofit and for storing it and fetching form db Room library. Both with the help of MVVM pattern. Is there a way to remoove the UI freeze?
Here is my code:
In the Mainactivity when clicking download btn
downloadBtn.setOnClickListener(v ->
eventsViewModel.insertEvents(this));
Viewmodel class:
public void insertEvents(Context context){
final SharedPreferences preferences = PreferenceManager.getDefaultSharedPreferences(context);
String token = preferences.getString("token", "");
final Map<String,String> queryData = new HashMap<>();
queryData.put("token", token);
Call<EventsResponse> call = RetrofitClient.getmInstance().getApi().getEvents(queryData);
call.enqueue(new Callback<EventsResponse>() {
#Override
public void onResponse(Call<EventsResponse> call, Response<EventsResponse> response) {
if (response.code() == 401){
String email = preferences.getString("email", "");
String password = preferences.getString("password", "");
Call<LoginResponse> call1 = RetrofitClient.getmInstance().getApi().loginuser(email, password);
call1.enqueue(new Callback<LoginResponse>() {
#Override
public void onResponse(Call<LoginResponse> call, Response<LoginResponse> response) {
if (response.code() == 200){
SharedPreferences pref = PreferenceManager.getDefaultSharedPreferences(context); // 0 - for private mode
SharedPreferences.Editor editor = pref.edit();
editor.putString("token", response.body().getToken());
editor.apply();
insertEvents(context);
}
else {
}
}
#Override
public void onFailure(Call<LoginResponse> call, Throwable t) {
}
});
}
if (response.code() == 200){
eventList = response.body().getData();
EventsTable eventsTable = new EventsTable();
TicketDatesTable ticketDatesTable = new TicketDatesTable();
for (int i = 0; i < eventList.size(); i++) {
eventsTable.setEvent_id(eventList.get(i).getId());
eventsTable.setTitle_tk(eventList.get(i).getTitle_tk());
eventsTable.setTitle_ru(eventList.get(i).getTitle_ru());
eventsTable.setImageURL("https://bilettm.com/" + eventList.get(i).getImage_url());
eventsTable.setStart_date(eventList.get(i).getStart_date());
eventsTable.setEnd_date(eventList.get(i).getEnd_date());
eventsTable.setSales_volume(eventList.get(i).getEnd_date());
eventsTable.setOrganiser_fees_volume(eventList.get(i).getOrganiser_fees_volume());
eventsTable.setViews(eventList.get(i).getViews());
eventsTable.setSales_volume(eventList.get(i).getSales_volume());
eventsTable.setIs_live(eventList.get(i).getIs_live());
if (!eventList.get(i).getTicket_dates().isEmpty()) {
showTimeList = eventList.get(i).getTicket_dates();
int b = 0;
while (b < showTimeList.size()) {
ticketDatesTable.setEvent_id(showTimeList.get(b).getEvent_id());
ticketDatesTable.setTicket_date(showTimeList.get(b).getTicket_date());
insertTicketDates(ticketDatesTable);
try {
Thread.sleep(150);
} catch (InterruptedException ex) {
Thread.currentThread().interrupt();
}
b++;
}
}
insert(eventsTable);
try {
Thread.sleep(150);
} catch (InterruptedException ex) {
Thread.currentThread().interrupt();
}
}
}
}
#Override
public void onFailure(Call<EventsResponse> call, Throwable t) {
}
});
}
public void insert(EventsTable data){
repository.insertEvents(data);
}
public void insertTicketDates(TicketDatesTable ticketDatesTable){
repository.insertTicketDates(ticketDatesTable);
Here is my repository :
public void insertEvents(EventsTable data){
new EventInsertion(eventsDAO).execute(data);
}
private static class EventInsertion extends AsyncTask<EventsTable, Void, Void> {
private EventsDAO eventsDAO;
private EventInsertion(EventsDAO eventsDAO) {
this.eventsDAO = eventsDAO;
}
#Override
protected Void doInBackground(EventsTable... eventsTables) {
eventsDAO.insertEvents(eventsTables[0]);
return null;
}
}
public void insertTicketDates(TicketDatesTable data){
new TicketDatesInsertion(eventsDAO).execute(data);
}
private static class TicketDatesInsertion extends AsyncTask<TicketDatesTable, Void, Void> {
private EventsDAO eventsDAO;
private TicketDatesInsertion(EventsDAO eventsDAO) {
this.eventsDAO = eventsDAO;
}
#Override
protected Void doInBackground(TicketDatesTable... ticketDatesTables) {
eventsDAO.insertTicketDates(ticketDatesTables[0]);
return null;
}
}
Here is my DAO:
#Insert(onConflict = OnConflictStrategy.REPLACE)
void insertEvents(EventsTable data);
#Insert(onConflict = OnConflictStrategy.REPLACE)
void insertTicketDates(TicketDatesTable datesTable);
I think it freezes when it is storing it into sqlite db

I found my problem. It was initializing entity before starting for loop:
BEFORE:
EventsTable eventsTable = new EventsTable();
for (int i = 0; i < eventList.size(); i++) {
INSERT();
}
AFTER:
for (int i = 0; i < eventList.size(); i++) {
EventsTable eventsTable = new EventsTable();
INSERT();
}

A better solution would be to collect all your required objects in an ArrayList and then pass it on to the AsyncTask and from there to DAO for bulk insertion.
And remove all Thread.sleep(150) statements as they serve no purpose.

why you are using this Thread.sleep(150);Call is already a background task in retrofit

Get data from server using of AsyncTask

In my program a number of values are stored on the server.
I read these data using of the AsyncTask class from the server.
This is my code:
public class TestActivity extends AppCompatActivity {
private static List<String> mPackName;
#Override
protected void onCreate(#Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mPackName = new ArrayList<>();
try {
boolean check = new GetDataAsyncTask().execute("1234567").get();
} catch (InterruptedException e) {
} catch (ExecutionException e) {
e.printStackTrace();
e.printStackTrace();
}
}
private class GetDataAsyncTask extends AsyncTask<String, Void, Boolean> {
#Override
protected Boolean doInBackground(String... params) {
final String mCode = params[0];
APIGettingPosts apiGettingPosts = new APIGettingPosts(TestActivity.this, "get_off_code.php");
apiGettingPosts.getOffCode(new APIGettingPosts.OnOffCodeReceived() {
#Override
public void onReceived(List<Posts> posts) {
if (!(posts == null || posts.isEmpty()))
for (int i = 0; i < posts.size(); ++i) {
mPackName.add(posts.get(i).getTitle());
Log.e("mPackName["+String.valueOf(i)+"]",mPackName.get(i));
}
}
});
Log.e("Size of mPackName: ", String.valueOf(mPackName.size()));
for (int i = 0; i < mPackName.size(); ++i)
if (mCode.equals(mPackName.get(i))) {
Log.e("Is Equal: ", mPackName.get(i));
return true;
}
return false;
}
}
}
The program correctly receives the data from the server and stores it in the mPackName list. At the end of the doInBackground function, the program checks if the input value in the GetDataAsyncTask().execute("1234567") function exists in the mPackName list, returns the true value.
Although the input value of the GetDataAsyncTask().execute("1234567") function is in the mPackNamelist, the program returns the false value.
The Log cat output is as follows:
08-28/com.green E/Size of mPackName:: 0
08-28/com.green E/mPackName[0]: 1234567
08-28/com.green E/mPackName[1]: QAZXSWE
08-28/com.green E/mPackName[2]: QWERTYU
The size of the mPackName list is also zero in Log cat , although it has three values {'1234567','QAZXSWE','QWERTYU'}.
The question is: How do I search '1234567' value in the mPackName list to return the true value in check = new GetDataAsyncTask().execute("1234567").get();
code?

Edited Answer
Looks like you even don't need AsyncTask as getOffCode method already runs in background thread.
Remove GetDataAsyncTask class and create a method like below.
private void search(final SearchCallback callback) {
APIGettingPosts apiGettingPosts = new APIGettingPosts(TestActivity.this, "get_off_code.php");
apiGettingPosts.getOffCode(new APIGettingPosts.OnOffCodeReceived() {
#Override
public void onReceived(List<Posts> posts) {
if (!(posts == null || posts.isEmpty())) {
for (int i = 0; i < posts.size(); ++i) {
mPackName.add(posts.get(i).getTitle());
Log.e("mPackName[" + String.valueOf(i) + "]", mPackName.get(i));
if (mCode.equals(mPackName.get(i))) {
callback.onSearchFound(true);
break;
}
}
}
callback.onSearchFound(false);
}
});
}
public interface SearchCallback{
void onSearchFound(boolean success);
}
Then call from onCreate method like below
search(new SearchCallback(){
#Override
public void onSearchFound(boolean success) {
}
});

Try placing a switch in the onPostExecute() method.
EG.
...
private class GetDataAsyncTask extends AsyncTask<String, Void, Boolean> {
#Override
void onPostExecute(Object o){
handleResults()
}
...
void handleResults(){
// Insert your check here
}

Android AsyncTask json return value

I have called an async task from my button click.In the doInBackground I have called an API and It is returning me a Json object.I want to pass the Json object to another activity on the button click.How can I can get the return Json object value so that I can send it to other activity.
Thanks.

Create Interface
public interface Listener {
void success(BaseModel baseModel);
void fail(String message);
}
Create Base model class
public class BaseModel implements Serializable {
private static final long serialVersionUID = 1L;
}
Call below method inside your onClick mehtod.
protected void userLoginData(final String userName) {
// if you want to pass multiple data to server like string or json you can pass in this constructor
UserLoginLoader userLoginLoader = new UserLoginLoader(LoginActivity.this, userName, "1234567899", new Listener() {
#Override
public void success(BaseModel baseModel) {
// here you got response in object you can use in your activity
UserLoginModel userLoginModel = (UserLoginModel) baseModel;
// you can get data from user login model
}catch(Exception exception){
exception.printStackTrace();
Utils.showAlertDialog(LoginActivity.this, "Server is not responding! Try Later.");
}
}
#Override
public void fail(String message) {
}
});
userLoginLoader.execute();
}
:- User Login Loader class
public class UserLoginLoader extends AsyncTask<String, Void, Boolean> {
private Dialog dialog;
private Listener listner;
private String deviceId;
Activity activity;
String message;
String userName;
boolean checkLoginStatus;
public UserLoginLoader(Activity activity,String userName, String deviceId, Listener listener) {
this.listner = listener;
this.userName =userName;
this.activity = activity;
this.deviceId = deviceId;
}
#Override
protected Boolean doInBackground(String... arg0) {
//User login web service is only for making connection to your API return data into message string
message = new UserLoginWebService().getUserId(userName, deviceId);
if (message != "null" && !message.equals("false")) {
return true;
}
return false;
}
#Override
protected void onPreExecute() {
super.onPreExecute();
dialog = new Dialog(activity, R.style.CustomDialogTheme);
dialog.setContentView(R.layout.progress);
dialog.setCancelable(false);
dialog.show();
}
#Override
protected void onPostExecute(Boolean result) {
super.onPostExecute(result);
BaseModel baseModel = null;
if (!message.equals("null") && (!message.equals("false")) )
baseModel = parseData(message, result);
if (dialog.isShowing()) {
dialog.dismiss();
dialog.cancel();
dialog = null;
}
if (listner != null) {
if (result && baseModel != null)
listner.success(baseModel);
else
listner.fail("Server not responding! Try agian.");
} else
listner.fail("Server not responding! Try agian.");
}
//call parser for parsing data return data from the parser
private BaseModel parseData(String responseData, Boolean success) {
if (success == true && responseData != null
&& responseData.length() != 0) {
UserLoginParser loginParser = new UserLoginParser(responseData);
loginParser.parse();
return loginParser.getResult();
}
return null;
}
}
This is you Login parser class
public class UserLoginParser {
JSONObject jsonObject;
UserLoginModel userLoginModel;
/*stored data into json object*/
public UserLoginParser(String data) {
try {
jsonObject = new JSONObject(data);
} catch (JSONException e) {
Log.d("TAG MSG", e.getMessage());
e.printStackTrace();
}
}
public void parse() {
userLoginModel = new UserLoginModel();
try {
if (jsonObject != null) {
userLoginModel.setUser_name(jsonObject.getString("user_name")== null ? "": jsonObject.getString("user_name"));
userLoginModel.setUser_id(jsonObject.getString("user_id") == null ? "" : jsonObject.getString("user_id"));
userLoginModel.setFlag_type(jsonObject.getString("flag_type") == null ? "" : jsonObject.getString("flag_type"));
} else {
return;
}
} catch (Exception exception) {
exception.printStackTrace();
}
}
/*return ship name list which is stored into model */
public UserLoginModel getResult() {
return userLoginModel;
}
}

Write a callback method in the Activity that takes in the argument that you wish to pass from AsyncTask to that Activity. Send reference to the Activity to AysncTask while creating it. From doInBackground() method make a call to this callback method with the data your API returns.
Code would be something like -
public class TestAsyncTask extends AsyncTask<Integer, Integer, String[]> {
Activity myActivity;
public TestAsyncTask(Activity activity) {
this.myActivity = activity;
}
#Override
protected String[] doInBackground(Integer... params) {
String data = yourApi();
myActivity.callback(data);
}
}
public class MyActivity extends Activity {
#Override
protected void onCreate(Bundle savedInstanceState) {
new TestAsyncTask(this).execute(someId);
}
public void callback(String data) {
//process data
}
}
Just for the record you can directly get return value from doInBackground() method by calling get() on it.
String data = new TestAsyncTask(this).execute(someId).get();
But note this may block your UI thread as it will wait for the doInBackground() method to complete it's execution.

Get information of object in mainactivity from class

I would like to use the information of 'result' in the XMLRPCMethod. When the thread is finished the correct data is in the result object.
This is a code snipped from my OpenerpRPC.java class.
class XMLRPCMethod extends Thread {
private String method;
private Object[] params;
private Handler handler;
public Object result;
private OpenerpRpc callBack;
public XMLRPCMethod(String method, OpenerpRpc callBack) {
this.method = method;
this.callBack = callBack;
handler = new Handler();
}
public void call() {
call(null);
}
public void call(Object[] params) {;
this.params = params;
start();
}
#Override
public void run() {
try {
result = client.callEx(method, params);
handler.post(new Runnable() {
public void run() {
try {
callBack.resultcall(result);
} catch (XMLRPCException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
});
} catch (final XMLRPCFault e) {
handler.post(new Runnable() {
public void run() {
Log.d("Test", "error", e);
}
});
} catch (final XMLRPCException e) {
handler.post(new Runnable() {
public void run() {
Throwable couse = e.getCause();
if (couse instanceof HttpHostConnectException) {
Log.d(TAG, "error"+uri.getHost());
} else {
Log.d("Test", "error", e);
}
Log.d("Test", "error", e);
}
});
}
}
}
My result call in the OpenerpRpc class looks like:
public void resultcall(Object result) throws XMLRPCException{
allres=result;
if (rtype.equals("login")){
//Isn't impossible cast the result var with (String) because cause crash..why?
userid=""+result;
}
if (rtype.equals("read")){
//Isn't impossible cast the result var with (String) because cause crash..why?
// userid=""+result;
}
// name of callback function to use in parent class (MainActivity) for receive data
this.parent.oerpcRec(rtype,allres);
}
This is how i can receive the data in mainactivity
#SuppressWarnings("unchecked")
public void oerpcRec(String rtype,Object res) throws XMLRPCException{
if (rtype=="login"){
connector.setModel("res.users");
Object[] Ids = {Integer.parseInt(connector.userid)};
// set here the fields you wont loads
Object[] values={"name"};
connector.Read(Ids,values);
}
if(rtype=="read"){
Object[] ret=(Object[])res;
Map<String, Object> map1 = (Map<String, Object>) ret[0];
if(ret.length > 1){
}
}
}
But how can i get this information in my mainactivity? I only get the information of the login id value. When I put a breakpoint in the thread it only goes to the function resultcall when I try to login.
...
public void onClick(View v) {
try {
//here set user and pass for login
connector.Login(USER,PASS);
Object[] ids = {31,30,28,26};
Object[] params ={"partner_id","tax_line","section_id","invoice_line"};
connector.Read(ids,params);
//get information of openERP for specific id's
} catch (XMLRPCException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}

Use an interface
public interface MyListener {
public void callback(Object result);
}
Your MainActivity must implement the interface
public class MyActivity extends Activity implements MyListener {
...
...
...
#override
public void callback(Object result) {
// getting the result value.
}
}
So when your thread finish, execute the callback() method:
MyListener ml;
ml.callback(result);
and the callback() method of you MainActivity will receive the object.

Android UI, Networking and async code

I have a serious problem which I can't a solution to.
I need to authenticate a token in order to let the user login into my app, the problem is that even though I'm using the AsyncTask, and probably because of it, I can't authenticate it in time. Other problem that sometimes accurs is that I get the NetworkOnMainThreadException error... I'm really hopeless.
Here's the flow -
Check for existsing token -> Validate -> Move to next activity
And here's my code -
public boolean validateToken(TokenAccess token) {
new IsValid().execute(token);
return isValid;
}
private class IsValid extends AsyncTask<TokenAccess, Void, Boolean> {
#Override
protected Boolean doInBackground(TokenAccess... params) {
TokenAccess token = params[0];
switch (token.getSource().getSource()) {
case 'M':
new UrlDownloader(new UrlDownloader.DownloadListener() {
#Override
public void setRequest(HttpRequest request) {}
#Override
public void onRecive(String content) {
if (content.contains("stats")) {
isValid = true;
} else {
isValid = false;
}
}
#Override
public void onError(Exception e) {}
}, UrlDownloader.RequestType.GET)
.execute("https://api.meetup.com/dashboard?access_token="
+ token.getToken());
}
return isValid;
}
}
That's is the URLDownloader class -
public class UrlDownloader extends AsyncTask<String, Void, HttpResponse> {
public static final String TAG = "net.ytsweb.socigo.assests.UrlDownloader";
public enum RequestType {
GET, POST;
}
private RequestType type;
private DownloadListener listener;
public UrlDownloader(DownloadListener listener, RequestType type) {
this.type = type;
this.listener = listener;
}
#Override
protected HttpResponse doInBackground(String... params) {
HttpClient httpClient = new DefaultHttpClient();
HttpUriRequest request;
HttpResponse response;
if (type == RequestType.GET) {
request = new HttpGet(params[0]);
} else {
request = new HttpPost(params[1]);
}
listener.setRequest(request);
try {
response = httpClient.execute(request);
} catch (Exception e) {
listener.onError(e);
return null;
}
return response;
}
#Override
protected void onPostExecute(HttpResponse response) {
try {
Log.d(TAG, response.getAllHeaders()[0].getValue() + "");
listener.onRecive(EntityUtils.toString(response.getEntity()));
} catch (Exception e) {
listener.onError(e);
}
}
public interface DownloadListener {
public void onRecive(String content);
public void onError(Exception e);
public void setRequest(HttpRequest request);
}
}

You need to use onPostExecute for handling the result of the IsValid AsyncTask. What I don't understand: why two AsyncTasks? One would be enough, do everything in there, and handle the result in the one and only onPostExecute.
Whatever happens in doInBackground is in a separate thread, onPostExecute happens on the UI-thread again. One AsyncTask is enough, but don't fetch a result in your validateToken method. In there, just execute your AsyncTask and whatever you need to do with the result you have to initiate in the onPostExecute.
As a basic example of what I mean:
public boolean validateToken(TokenAccess token) {
new YourAsyncTask().execute(token);
// DON'T rely on a result here
}
public class YourAsyncTask extends AsyncTask<?, ?, ?> {
#Override
protected ? doInBackground(?) {
// do networking in background-task
return result;
}
#Override
protected void onPostExecute(? response) {
// handle result here.. call a method in your main class, a listener with the result, or start an Activity directly
}
}